Trolley head for electric tramcars



Dec. 18,1923. wimw F. SHARP ET AL.

TROLLEY HEAD 'FOR ELECTRIC TRAMCARS Filed AHZ- 4, 1921 INVENTORS,

FRED SHA RP,

- JbH/v MART/IV,

i atented Dec. 12 3, I923.

TROLLEY HEAD FOR ELECTRIC TRAMCARS.

Application filed August 4, 1921.

Serial No. 489,907.

(GRANTED UNDER THE PROVISIONS OF THE ACT OF MARCH 3, 1921, 41 STAT. L., 1313.)

To all whom it may concern:

Be it known that we, FRED SHARP and JOHN MARTIN, both subjects of the King of Great Britain, residing at Barrow-in-Furness, Lancashire, England, have invented certain new and useful Improvements in Connection with Trolley I-Ieads for Electric Tramcars (for which application has been filed as follows: Great Britain, Nov. 3, 1919, Patent No. 1%,183), of which the following is a specification.

This invention relates to trolley heads for electric tram cars of the kind in which a shield is disposed upon each side of the pulley so as to project above the same which shields are pivotally mounted upon the axis pin of the trolley pulley and held in normal vertical position by spring means in such a manner that such shields can turn backwards against the spring pressure when encountering an obstacle. The object of these shields is to prevent the pulley from leaving the cable when meeting an obstacle such as the usual supporting frogs.

According to the present invention the shields are formed integral with each other and comprises a pair of upstanding or vertically disposed ears the upper extremities of which constitute the shields whilst the lower extremities constitute the points of pivotal connection with the axis pin of the pulley. A channel shaped arm is formed integral with said ears and extends rearwardly therefrom and approximately at right angles thereto for a convenient distance in which position it is normally main tained by a compression spring.

Upon meeting an obstruction the ears are turned about their pivot the arm being similarly depressed against the action of the compression spring which operates to return the shields to their normal position when the obstruction is passed.

In order that the invention may be clearly understood the same will now be described by aid of the accompanying drawings in which 1- Fig. 1 is a side elevation and Fig. 2 and end elevation of'the device constructed in accordance with the present invention.

Fig. 3 is a view illustrating the rope attachment for manipulating the trolley.

In the drawings a indicates the trolley head which is of the ordinary construction and in which the device forming the subject of this invention is fitted. The device consists of a channelled member 6 made of brass which is at one end pivotally mounted on the axle of the pulley wheel or sheave 0 and having its sides at that end projecting upwardly see 03 Figs. 1 and 2 a suitable extent, with the outer surfaces of the projections at in frictional contact with the sides of the trolley head a.

A compression spring 6 arranged around a bolt or pin f fixed at its lower end to a plate or bearer g fixed to a lug h on the trolley head has its upper end passed through a hole formed in the bottom of the channeled member I). The bolt or pin f is screw threaded at its free end and a nut 2' screwed thereon to retain said pin or bolt in position in the hole in the channelled member I). The lower end of the spring rests against the plate or bearer 9 while its upper end bears against the under surface of the channel I) and said spring e is placed under compression to the required extent to maintain the projections (Z of the channelled member Z) in contact normally with the cable.

lVhen any obstruction on the cable is met with the projecting sides (I of the channelled member B make contact therewith and con sequently the member .7) turns upon its axis in the direction of the arrow shown in Fig. 1. This movement depresses the channel 6 and the spring 6 is compressed. The depression of the channel B permits of the trolley head passing the obstruction and when it has cleared this obstruction the spring 6 expands and returns the member I) no normal position.

The rope hole is constituted by an eyebolt j on the lug 7t and to the eye j of this bolt the end 70 of a pair of wires are attached, the free ends 70' being outstretched to form a triangle with a stiffening wire Z as a base. At the free ends 70 loops or rings on are fixed and to these rings at the operating lines 11. are connected (see Fig. 3).

We declare that what we claim is In a trolley head, the combination of a forked frame, a journal pin connecting the arms of said frame, a trolley wheel journaled on said pin, rotatable shield members also journaled on said pin between each arm of the frame and the adjacent side of the trolley wheel adapted in normal position to project above the Wheel to prevent latatits ends against said bracket and said Iilllfl eral disengagement of a trolley Wire there tual connection,respectively, to hold said inufrom, mutually connecting arms projecting tual connection against said stop whereby from the shield, a bracket on said forked the shields are held in normal position and i5 5 frame, a rod secure? at 011181) end tlo IS'cElCl permitted to yield in one direction.

bracket and at its ot ier enc eing sica le through the mutual connection of said arms, a stop on the last mentioned end of said rod l V to limit rotative movement of said arms and Signed in the presence of 10 said shields in one direction, a compression ALFRED BARROW, spring surrounding said rod and bearing T. A. MORGAN. 

